In addition to office/openoffice/libreoffice tools (that can surely be ok) there are software systems for mind map (you find some through google). They could help organizing your map all right. Probably they also impose some structure on you, which you might not like.
Another option is in the software tools for conceptual mapping, one of which I know of is cmapTools, that seems quite ok too.
I used a mind mapping software called "Inspiration" but really did not like it. I found that I could accomplish the same results with Visio. To develop problem-solving abilities (a question that you did not ask), there is nothing like the game of chess :)
hi aia studied this staff during my PhD course work on Knowledge value chain and you will certainly find a template in a standard text book on Knowledge management.
Mind mapping tools can be useful for some tasks. See for example, the free tool at http://cmap.ihmc.us/download/
However, they are useful only for capturing declarative knowlegde, and are not great for capture of strategic or procedural knowledge. For the latter, a simple outliner or hierarchy planner (e.g., using OmniGraffle) can be better.